Oracle 5.0, Справочное руководство

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Getting
memcached
Statistics
1386
Statistic Description Version
decr_hits
Number of decrement hits to this chunk 1.3.x
cas_hits
Number of CAS hits to this chunk 1.3.x
cas_badval
Number of CAS hits on this chunk where the existing value did not
match 1.3.x
mem_requested
The true amount of memory of memory requested within this
chunk 1.4.1
The following additional statistics cover the information for the entire server, rather than on a chunk by
chunk basis:
Statistic Description Version
active_slabs
Total number of slab classes allocated.
total_malloced
Total amount of memory allocated to slab pages.
The key values in the slab statistics are the
chunk_size
, and the corresponding
total_chunks
and
used_chunks
parameters. These given an indication of the size usage of the chunks within the
system. Remember that one key/value pair is placed into a chunk of a suitable size.
From these stats, you can get an idea of your size and chunk allocation and distribution. If you store
many items with a number of largely different sizes, consider adjusting the chunk size growth factor
to increase in larger steps to prevent chunk and memory wastage. A good indication of a bad growth
factor is a high number of different slab classes, but with relatively few chunks actually in use within
each slab. Increasing the growth factor creates fewer slab classes and therefore makes better use of
the allocated pages.
15.6.4.3.
memcached
Item Statistics
To get the
items
statistics, use the
stats items
command, or the API equivalent.
The
items
statistics give information about the individual items allocated within a given slab class.
STAT items:2:number 1
STAT items:2:age 452
STAT items:2:evicted 0
STAT items:2:evicted_nonzero 0
STAT items:2:evicted_time 2
STAT items:2:outofmemory 0
STAT items:2:tailrepairs 0
...
STAT items:27:number 1
STAT items:27:age 452
STAT items:27:evicted 0
STAT items:27:evicted_nonzero 0
STAT items:27:evicted_time 2
STAT items:27:outofmemory 0
STAT items:27:tailrepairs 0
The prefix number against each statistics relates to the corresponding chunk size, as returned by the
stats slabs
statistics. The result is a display of the number of items stored within each chunk within
each slab size, and specific statistics about their age, eviction counts, and out of memory counts. A
summary of the statistics is given in the following table.
Statistic Description
number
The number of items currently stored in this slab class.
age
The age of the oldest item within the slab class, in seconds.
evicted
The number of items evicted to make way for new entries.
evicted_time
The time of the last evicted entry
evicted_nonzero
The time of the last evicted non-zero entry 1.4.0